江西地区24例罕见β-地中海贫血患者基因型分析  

Genetic analysis of 24 rare cases ofβ-Thalassemia in Jiangxi area

作　　者：罗海艳 刘艳秋[1] 谢康[1] 邹永毅 陆清[1] LUO Haiyan;LIU Yanqiu;XIE Kang;ZOU Yongyi;LU Qing(Prenatal diagnostic center of Jiangxi maternal and child health hospital,Nanchang330000,China)

机构地区：[1]江西省妇幼保健院产前诊断中心,江西南昌330000

出　　处：《实验与检验医学》2020年第3期466-469,共4页Experimental and Laboratory Medicine

基　　金：江西省卫生计生委科技计划,编号20185387。

摘　　要：目的对常规基因检测结果与表型不符的β-地中海贫血(简称β-地贫)高风险患者(MCV<80fl、MCH<27pg,HbA2>3.5%)行β-珠蛋白基因分析,降低β-地贫的漏检率及误诊率,同时了解江西地区罕见β-地贫的基因突变类型及频率,丰富江西地区β-地贫基因突变谱。方法采用跨越断裂点聚合酶链反应(Gap-PCR)与Sanger测序技术对24例表型与基因型不符的β-地贫高危患者行β-珠蛋白基因大片段缺失与点突变分析。结果 24例患者均检出罕见β-珠蛋白基因突变,共9种突变类型。其中缺失型突变4例,β-台湾型缺失地贫(Taiwan Residents)及β-东南亚缺失地贫(SEA-HPFH)各2例。罕见点突变型20例,共7种突变类型。点突变CD54-58(-TATGGGCAACCCT)β0杂合突变人次共计8例,检出率高达33.3%(8/24),-31 (A>G)β+杂合突变人次共计3例,检出率高达12.5%(3/24)。结论江西地区罕见β-地贫基因突变类型中,CD54-58(-TATGGGCAACCCT)β0突变与-31(A>G))β+突变频率较高;对表型与基因型不符的β-地贫高危患者行进一步基因分析可发现罕见β-地贫基因突变,为β-地贫携带者家系的遗传咨询与产前诊断提供重要支持。Objective To determine the rare mutations ofβ-globin gene in patients with high risk ofβ-Thalassemia(MCV<80fl,MCH<27pg,HbA2>3.5%)who were negative for routine gene detection,to reduce the omission ratio and misdiagnosis rate ofβ-Thalassemia,and meanwhile to broaden the mutation spectrum ofβ-Thalassemia in Jiangxi area.Methods Gap-PCR and Sanger sequencing were used to analyze large deletions and point mutations ofβ-globin gene for 24 patients whose phenotypes were not consistent with their genotypes.Results The 24 cases were all detected with rareβ-globin gene mutations,a total of 9 mutant types.4 subjects were detected with large deletions,2 with Taiwan Residents and 2 with SEA-HPFH deletion.Twenty subjects were detected with rare point mutations,including 7 mutant types.Among the 20 subjects,8 cases were identified as CD54-58(-TATGGGCAACCCT)β0 heterozygote,3 cases were identified as-31(A>G)β+heterozygote,suggesting a relatively high mutation frequency.Conclusion Further genetic analysis of rareβ-globin gene mutation can help to discover rare mutations and identify the genotypes,thus providing important support for genetic counseling and prenatal diagnosis.

关 键 词：地中海贫血 Β-珠蛋白基因 Gap-PCR Sanger测序 

分 类 号：R393[医药卫生—基础医学] R556.61